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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Flood estimation for roads, bridges and dams. / Flood estimation for roads, bridges and dams.

Parak, Mohamed. 20 October 2010 (has links)
Flood estimation can be classified into two categories, i.e. flood prediction and flood forecasting. Flood prediction is used for the estimation of design floods, which are floods associated with a degree of risk of being equalled or exceeded. Predictions are needed for the design and construction of infrastructure that are at risk to flowing water. Flood forecasting is used for the estimation of flood flows from an impending and/or occurring rainfall event (i.e. the estimation of the magnitude of future flood flows with reference to a specific time in the future). These are needed by catchment and disaster managers for the mitigation of flood damage. The estimation of flood magnitudes for flood forecasting requires the specific knowledge of prevailing surface conditions which are associated with the processes of rainfall conversion into flood runoff. In order to best achieve this, a distributed model (in order to exploit remotely sensed data and capture the spatial scale of the phenomenon) is used to continuously update the surface conditions that are important in this conversion process. This dissertation focuses on both flood estimation categories. In the first part of the dissertation, attention is given to the improvement of two simple event-based design flood prediction methods currently in use by design practitioners, namely the regional maximum flood (RMF) and the rational formula (RF) by comparison with statistically modelled historical flood data. The second part of the dissertation lays the theoretical and practical foundation for the implementation of a fully distributed physically-based rainfall-runoff model for real-time flood forecasting in South Africa. The TOPKAPI model was chosen for this purpose. This aspect of the research involved assimilating the literature on the model, testing the model and gathering and preparing of the input data required by the model for its eventual application in the Liebenbergsvlei catchment. The practical application of the model is left for a follow-up study. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, 2007. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, 2007
32

Geodynamic Origin of the Columbia River Flood Basalts

Perry-Houts, Jonathan 30 April 2019 (has links)
Tertiary history of the Pacific Northwest is closely tied to that of the Columbia River Flood Basalt (CRB) events. The region is, geologically, one of the least well understood parts of the continental United States. Throughout the Neogene, the Columbia Basin and surrounding terrains appear to have been shaped not by horizontal tectonic forces, but by deep dynamic forcing, driving apparent “vertical tectonics.” This class of phenomena appears to be at odds with the traditional tenets of plate tectonics, and yet may prove to be ubiquitous geologic processes worldwide. Many of the processes described here are unique to volcanically-active regions, such as those affected by CRB eruptions and deposition. In the following chapters I will discuss several physical mechanisms by which lithosphere can deform in the absence of horizontal tectonic stress. These include analyses of the mechanisms associated with metamorphic densification, rheologic transformation owing to magmatic intrusions, and the dynamics of lithospheric delamination. All code and documentation to reproduce the results presented here can be found in the supplemental files included with this dissertation. Appendices A and B document the purpose, usage, and functionality of each supplementary file. This dissertation includes previously published and unpublished coauthored material.
33

Prediction of peak flows for culvert design on small watersheds in Oregon /

Campbell, Alan J. January 1981 (has links)
Thesis (M.S.)--Oregon State University, 1982. / Map folded in pocket. Typescript (photocopy). Includes bibliographical references (leaves 61-65). Also available on the World Wide Web.
34

Associations between hydrological connectivity and resource partitioning among sympatric gar species (Lepisosteidae) in a Texas river and associated oxbows

Robertson, Clinton Ray 15 May 2009 (has links)
The middle Brazos River, located in east central Texas, is a meandering lowland river that contains many oxbow lakes on its floodplain. Flood dynamics of the Brazos River are aseasonal, and faunal exchange during lateral connections of the main river channel and oxbows is pulse-like and only occurs during floods that may be months or years apart. Patterns of resource use among sympatric gar species (Lepisosteus oculatus, L. osseus, and Atractosteus spatula) associated with river-floodplain connectivity was studied for a period of two years (May 2003 to May 2005). The first year was relatively dry yielding few lateral connections, whereas the second year was relatively wet resulting in more frequent lateral connections. This study focused on habitat and diet partitioning among the three gar species in oxbow habitats with different connection frequencies and an active river channel site. Overall, 684 gars were collected with experimental gillnets: 19 A. spatula (alligator gar), 374 L. oculatus (spotted gar), and 291 L. osseus (longnose gar). There was strong partitioning of habitat between spotted and longnose gars, in which 98% of spotted gars were captured in oxbow habitats and 84% of longnose gars were captured in the river channel. Hydrology did not appear to affect habitat partitioning, although longnose gar abundance significantly increased in oxbows during the wet year. Diet overlap was high between spotted and longnose gars. Temporal variation in diet was significantly influenced by flood pulses that connected oxbows with the river channel, and which allowed predators and their prey to move between habitats.
35

Development control on floodplain in Hong Kong : a flood mitigation viewpoint /

Chow, Yum-yuet, Francis. January 1995 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1996. / Includes bibliographical references (leaves 79-82).
36

A state space model for river routing

Baltas, Evangelos A. 08 1900 (has links)
No description available.
37

Floods, flood damage and flood risk assessment in tropical environments : A Jamaican case study

O'Hara, M. January 1988 (has links)
No description available.
38

Responding to flood risk in the United Kingdom : a strategic reappraisal

Priest, Sally Jane January 2003 (has links)
No description available.
39

Estimating residential flood control benefits using implicit price equations

Thompson, Mark Edward 05 June 1980 (has links)
Graduation date: 1981
40

Distributed rainfall-runoff modeling of thunderstorm-generated floods a case study in a mid-sized, semi-arid watershed in Arizona /

Michaud, Jene Diane. January 1992 (has links) (PDF)
Thesis (Ph. D.)--University of Arizona, 1992. / Includes bibliographical references.

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